Thermostatically controlled air blender



pril 3, 1956 EL ROY 1 KRAFTA 2,740,587

THERMOSTATICALLY CONTROLLED AIR BLENDER 3 Sheets-Sheet 1 F .L L?- lFiled Deo. 20, 1951 p 7 d @la w ttl n a a 2 a IIIIIII L f .,illl a April3, 1956 EL ROY J. KRAFT THERMOSTATICALLY CONTROLLED AIR BLENDER 3Sheets-Sheet 2 Filed Dec. 2O,` 1951 April 3, 1956 EL ROY J. KRAFTTHERMOSTATICALLY CONTROLLED AIR BLENDER 5 Sheets-Sheet 3 Filed Dec. 20,1951 Zfj ai.

United States THEOSTATICALLY CONTROLLED AIR BLENDER El Roy .l1 Krait,Des Plaines, lll., assigner to The Dole Valve Company, Chicago, Ill., acorporation of Illinois Application December 20, 1951, Serial N o.262,594

2 Claims. t (Cl. 237-2) This invention relates generally to Ventilatingapparatus and more particularly to a Ventilating system of the typeincluding a blending enclosure to receive the controlled expansion ofpressurized temperature conditioned air whereby a ow of air into theblending apparatus from a ventilated space in which the blendingapparatus is located is induced for mixture with the pressurizedtemperature conditioned expanded air prior to exiting from the blendingapparatus into the space being ventilated. This invention furtherrelates to improved thermostatic control means for regulating theexpansion of the pressur-ized temperature conditioned air into theblending apparatus.

According to the general principles of the present invention, a supplyof Ventilating air is temperature conditioned and pressurized for.distribution to one or more spaces to be ventilated. In order toimprove the overall eiciency ofthe temperature conditioning and airdistribution system, it may be desirable to temperature condition theair by imparting thereto a considerable quantity of thermal energy inexcess of the temperature level at which the supply of air could bedirected into an occupied space to be ventilated without subjecting theoccupants of the space to a discharge ow exceeding normal comfortlevels. It is further desirable to pressurize `the temperatureconditioned air to aconsiderable extent so as to facilitate the etcientdistribution of temperature conditioned air through small sized ducts,thereby `avoiding unnecessary thermal losses and unnecessary'tiowlosses.

There is provided by the present invention a blending apparatuscomprising an enclosure adapted to be placed in a space to be ventilatedand having at least a pair of spaced openings in one wall thereofplacing the interior of the enclosure in communication with the space tobe ventilated. A duct carrying the pressurized temperature conditionedair extends into the blending apparatus .enclosure and is provided withan .outlet adjacent one of the openings and projecting towards the other`of the lopenings. The vexpansion of pressurized temperature conditionedair from the duct in the enclosure is selectively controlled bytheprovision of a damper or .shutter device located in the duct outlet.Thus, `as expansion of the pressurized temperature conditioned airoccurs, the ,re-

`sultant high velocity low pressure ow of air into `the enclosure willinduce the ow ofair through the first opening from the space beingventilated whereupon such ,air will be thoroughly mixed and blendedwithin the enclosure. The mixed and blended air is then `dischargedthrough the other opening of the enclosure into the space beingVentilated.

This invention further contemplates the provision of an improvedthermostatic control device arranged to regulate the damper or shuttercontrolling the expansionof pressurized temperature conditioned air intothe blending chamber in response to temperature variations in the spacebeing ventilated. To V'efiect'this end, a casing having -a first passagehousing ashutter actuator is positioned kadjacent the ductoutlet.Thecasing -istprovided Iwith a 2,740,587 Patented Apr. 3, 1956 secondpassage intersecting the first passage and also intersecting one wall ofthe blending apparatus orblending chamber, thereby placing the casingpassages in communication with the space being ventilated. A crankpivotally connected to the casing has a first arm projecting -into thefirst passage and connected to the damper or shutter actuator and asecond arm projects into the second passage. A thermostat is located inthe second passage and is connected to the second arm. The casingfurther includes means to place the first passage Iin communication withthe duct fluid, the first passage having an outlet opening into theblending chamber whereupon flow of duct fluid through such outlet willinducethe flow of space temperatured air through the second passage pastthe thermostat, thereby to control the damper or shutterthermostatically.

It is an object of the present invention to provide a method of andAapparatus for distributing temperature conditioned air to a ventilatedspace by a thermostatically regulated blending apparatus.

Another object of the present invention is to provide anl improvedblending apparatus for blending high temperature high pressure liuidwith fluid from an adjacent enclosure.

A further object of the present invention is to provide an improvedmechanism for regulating an angularly d isplaceable shutter by means ofa thermostat located remotely from, the shutter.

Many other features, advantages and additional objects of the presentinvention will become manifest upon making reference to the detaileddescription which follows and the accompanying sheets of drawings whichshow a preferred structural embodiment incorporating the principles ofthe present invention and by means of which thesteps of the methoddisclosed herein may be practiced,

@n the drawings:

Figure l is a somewhat schematic View showing a temperature conditioningand air distribution system incorporating the principles of the presentinvention and by means of which the method disclosed herein may bepracticed;

Figure 2 is a `fragmentary elevational viev of a blending chamberprovided in accordance with the principles of the present invention;

Figure 3 is a fragmentary cross-sectional view taken lsubstantially online Ill-fili of Fig. 2;

`in elevation and with parts removed showing additional details ofconstruction or the thermostatically controlled shutter mechanismemployed in the blending ,apparatus of Figures 2 and 3; f

Figure 5 is a somewhat reduced elevational view of the structure shownin Figure 4;

Figure 6 is a cross-sectional plan View showing additional details ofconstruction `of the structure shown in Figures 4 and 5; and

Figure 7 is an exploded view of the control device shown in Figure 6with. parts shown in section] As shown on the drawings:

In Figure l is shown schematically a temperature conditioning airdistribution system embodying the principles of the present invention.An enclosure l@ is provided with a plurality of spaces to be ventilatedincluding a space ll and a space l2. A temperature conditioning unit orheat exchanger by way of illustrative structural embodiment takes theform of a furnace i3 having a plenum chamber ld. The 'furnace i3 .isprovided with a pressurizing means such as a blower i6 so thatpressurized temperature conditioned air may be furnished vto the plenumchamber i4.

A duct 1'7 leadsfrorn the plenum chamber l-t to a --blend-ing chamber i8having ,a vpai-r of-spaced apart openings in one wall thereofcommunicating with the space 11 The uppermost opening is indicated at 19and cornprlses an inlet for the blending chamber 1S while the lowerrnostopening is indicated at 20 and comprises an outlet for the blendingchamber 18. A flow control mechanism indicated generally at 21 isprovided to regulate the expansion of pressurized temperatureconditloned air from the duct 17 into the blending chamber 18.

A duct 22 leads from the plenum chamber 14 and communicates with ablending chamber 18a having a pair of spaced openings communicating withthe space 12, the lowermost opening indicated at 19a and comprising aninlet for the blending chamber 18a while the uppermost opening isindicated at 20a and comprises an outlet for the blending chamber 18a. Aow control mechanism indicated generally at 21 is also provided toregulate the expansion of pressurized temperature conditioned air fromthe duct 22 into the blending chamber 18a.

If desired, the usual cold air returns indicated at 23 may be extendedbetween the spaces 11 and 12 and th furnace 13.

The structural details of the blending chambers 18 and 18a shown more orless schematically in Figure l may be more clearly understood uponmaking reference to Figures 2 and 3 wherein is shown an illustrativestructural embodiment of a typical blending chamber provided inaccordance with the principles of the present invention. For the sake ofconvenience and clarity of understanding, it will be assumed that theblending chamber of Figures 2 and 3 corresponds with the blendingchamber 18a and similar reference numerals will be applied to thestructure of Figures 2 and 3. Thus, it will be noted that the blendingchamber 18a comprises an enclosure having a pair of spaced openings 19aand 20a in one wall thereof. The duct 22 extends into the blendingchamber 18a and is provided with an outlet 24 located adjacent theopening 19a and arranged to direct fluid into the enclosure comprisingthe blending chamber 18a in the general direction of the outlet 20a. Adamper or shutter 26 is provided in the outlet 24 of the duct 22 toregulate the expansion of pressurized temperature conditioned air intothe blending chamber 18a.

In order to improve the overall efficiency of the ternperatureconditioning and air distribution system, it may be desirable to supplyVentilating air which is heated to a relatively high temperature leveland pressurized to a relatively high pressure level. By so doing, thedistribution ducts employed in the system may be greatly reduced in sizethereby minimizing flow losses and thermal losses which would otherwiseoccur in a conventional temperature conditioning and air distributionsystem wherein the Ventilating air is heated to relatively lowtemperatures and pressurized to relatively low pressures. Under suchconditions, however, it will be apparent that the ventilating air cannotbe expanded directly into the space to be ventilated without subjectingthe occupants of the space to uncomfortable blasts of Ventilating airheated to a temperature above normal comfort levels.

According to the principles of the present invention, the pressurizedtemperature conditioned air expanded from the duct 22 at the outlet 24under the regulation of the shutter 26 produces a high velocity lowpressure flow into the blending chamber 18a which tends to induce theflow of air from the space 12 through the inlet opening 19a whereuponthe air from the space 12 and the expanded air from the duct 22 will bethoroughly mixed and blended within the blending chamber 18a and willsubsequently pass out through the outlet opening 20a. The mixed andblended air emanating from the outlet opening 20a will be at atemperature level consonant with the comfort requirements of the space12 and will also move at a reduced velocity so as to minimize thepossibilities of an uncomfortable air blast.

The present invention further contemplates the regulation and control ofthe expansion of air from the duct 22 in response to temperaturevariations within the space 12, such regulation and control beingeffected by means of the ilow control mechanism indicated generally at21.

Referring now more particularly to Figures 4-7 in connection withFigures 2 and 3, it will be noted that the duct 22 has assembledtherewith a bracket 27 which may be secured to the duct 22 in firmassembly by any conventional means, for example, spot welding as at 28.The bracket 27 is provided with a support section having a pair ofspaced apertures 29 and 30 each seating the looped end of a suspensionmember indicated at 31 and 32 respectively.

A retainer 33 is firmly connected to the shutter 26 by a pair offasteners 34 and includes an arm portion 36 arranged to extend through aplane parallel to a plane Y intersecting both of the apertures 29 and 30in the support section of the bracket 27. The arm 36 has a pair ofspaced apart recesses 37 and 38 which receive the opposite looped endsof the suspension members 31 and 32, respectively.

The retainer 33 is twisted as at 39 so that when the shutter 26 is inone predetermined position, vthe axis of the arm 36 and the axis of theapertures 29 and 30 will be relatively angularly offset thereby to twistthe suspension members 31 and 32 and torsionally loading the shutter 26.

The retainer 33 further includes a pair of arms 40 and 41 which projectfrom opposite ends of the arm 36 and which are arranged in generallyparallel relationship with respect to one another. A pair of clips 42and 43 are carried by the duct 22 and lie in spaced relationship to thearms 40 and 41 so that a pair of 'control springs 44 and 46 may beextended between the arm 40 and the clip 42 and between the arm 41 andthe clip 43, respectively,

At the opposite side of the shutter 26, a tensioning cord 47 is iirmlysecured as at 48 and extends through the wall of the duct 22. Thesuspension means supporting the shutter 26 torsionally load the shutter26 vand the tensioning cord 47 is effective to translate variabletensions to thev torsionally loaded shutter 26 thereby to control therelative angular displacement of the shutter` 26 in the duct 22. f

The flow control mechanism 21 includes a casing indicated generally at49 having a first passage 50 coaxially aligned relative to thetensioning cord 47 vso that one end of the tensioning cord 47 may bereceived thereby. The casing 49 further includes a second passage 51which intersects the first passage 50. In the preferred structuralembodiment herein shown, the second passage 51 is disposed at rightangles to the first passage 50.

Adjacent the point of intersection of thepassages 50 and 51 is provideda journaling means 52 seating a crank 53 having a first arm 54projecting into the first passage 50 and being connected in rm assemblywith the end of the tensioning cord 47 as at 56. The crank 53 isprovided with a second arm 57 which projects into the second passage 51.A pivot pin 58 pivotally journals the crank 53 on the journaling portionS2 of the casing 49, thereby permitting selective angular displacementof the crank 53. It will be appreciated that the movement of the crankarms 54 and 57 throughout a limited range will be substantially linearwith relationship to the Arespective passages 50 and 51, the angulardisposition of the crank arms 54 and 57 being similar to the relativeangular disposition of the first passage 50 and the second passage 51.

A retainer 59 is slotted as at 60 to receive the arm 57 and is alsoprovided with a recess 61 extending thereinto from one end to receiveand seat the end of a spacer 62. The other end of the retainer 59 isprovided .with a neck 63 arranged to bottom one'end of a coil spring64".

having its opposite end bottomed against the walls of the'casing 49, ahollow boss 66 being provided at the end of the passage 51 to receivetheend of the coil spring 64.

The spacerL-62 comprises-agenerallyylindricaLmem- .-ber. having 'aplurality `of-.radiallyV` extending "circumferone end of the housing 70a plurality of radially inwardly extending circumferentially spaced lugs72 are provided to abuttingly engage and seat an annular rib 73 formedon a thermal unit 74. The thermal unit 74 preferably comprises athermostat of the type enclosing a mass of material which will change involume during a transformation from one physical state to another inresponse to temperature variations, the relative changes in volume beingutilized to effect the linear translation of a movable piston member 76arranged to project out of one end of the thermal unit 74 for engagementwith the spacer 62. The spacer 62 is recessed endwise as at 77 to seatthe piston 76. A knurled adjusting knob 78 is firmly connected to thehousing 70 and may be rotated in alternative direction to selectivelyvary the effective thermal range of the thermal unit 74 through theaxial adjustment of the housing 70 relative to the casing 49.

The casing 49 is provided with a depending portion 79 having a thirdpassage 80 which intersects the duct 22 and communicates with the ductfluid on the upstream side of the shutter 26. An outlet opening S1communicating with the blending chamber 18a is provided for the thirdpassage Si). The third passage 80 is also placed in communication withthe first passage 50 by means of an aperture 82 so that flow of ductfluid through the third passage 86 into the blending chamber 18a by wayof the outlet 81 will induce the flow of air from the first passage 59through the aperture 82, thereby aspirating a dow of air through thesecond passage 51 past the thermal unit 7d.

By virtue of the angular relationship between the first passage l) andthe second passage 51, the casing 49 is advantageously,arranged with thesecond passage 51 intersecting the one wall of the blending chamber 18aso as to place the second passage 51 in communication with the air inthe space 12. Thus, as air is aspirated through the passage S1, thethermal unit 74 will be subliectcd to changes in temperature occurringin the fluid within the space 12.

The coil spring 64, of course, operates as a control spring and normallyurges the crank 53 in one direction, however, upon movement of thepiston 76 in response to variations in temperature within the space 12,the crank 53 will be moved against the bias of the spring 64 therebyaltering the tensioning force imparted to the torsionally suspendedshutter by the tensioning cord 47. it will be understood that wheneverthe tensioning force on the tensioning cord 47 is varied, the torsionalload on the shutter 26 will result in the shutter 26 assuming apredetermined position of equilibrium and any variation in the tensionalforce on the tensional cord 47 will upset such equilibrium so that theshutter will seek a new angular position corresponding to a new positionof equilibrium. In this manner, tensional variations are imparted to thetensioning cord 47 in response to teniperature variations within thespace 12 so as to open and close the shutter 26 thereby controlling andregulating the expansion or" the pressurized and temperature conditionedair from the duct 22 into the blending chamber 18.

In the preferred embodiment herein shown, the casing 49 is made in twoseparate halves which are connected together by a plurality of fasteners83. The casing 49 may be attached in rm assembly with the duct 22 bymeans of a suitable bracket S4 and an aperture 86 is Yprovidedthrough'which'y thetensioningrcordf-d? may be `passed.

As a` matter of interest it. may be noted .thatthe shutter `26 employedin the presentembodimentl isyoflgenerally Voval configurationandissomewhat angularlydisposed within. the' duct '322. v'To -facilitate..:c1osingaction, the edges of the shutter 26 are provided with a stripof flexible material 'indicated' at 88,-- -for example, felt. A pair ofspaced apartstruts :89 and Ware/extended across .the duct 22 toreinforce the duct structure in .the vicinity of the flow controlmechanism 21 and also serve as limit stops for the shutter 26.

Although various minor structural modifications might be suggested bythose versed in the art to the preferred structural embodiment hereindisclosed by way of illustrative example, it should be understood that Iwish to embody within the scope of the patent warranted hereon all suchmodifications as reasonably and properly come within the scope of mycontribution tothe art.

I claim as my invention:

1. A temperature conditioning system comprising a heat exchanger havinga plenum chamber to receive pressurized temperature conditioned fluid, aspace to be temperature conditioned, a housing in said space having apair of spaced apart apertures in one wall thereof cornmunicating withthe fluid in said space, a duct between said plenum chamber and saidhousing, said duct having an outlet extending into said housing adjacentone of said apertures and directed toward the other of said apertures, ashutter in said duct, means to rotate said shutter including an actuatorextending through one wall of said duct, a casing having a first passagereceiving said actuator and a second passage intersecting said firstpassage, said second passage also intersecting said one wall of saidhousing, a crank pivoted on said casing having one arm in said firstpassage connected to said actuator and a second arm in said secondpassage, a thermostat in said second passage engaging said second arm tocontrol said actuator thermostatically, said casing having a thirdpassage intersecting saidduct on the upstream side of said shutter andintersecting said first passage, said first passage having an outletopening into said housing in registry with saidthird passage, wherebythe flow of fluid from said duct through said outlet will induce a flowof fluid from said first passage thereby to aspirare fluid from saidspace through said second passage past said thermostat, the discharge offluid from said duct into said housing operating to induce a flow offluid from said space through said one aperture into said housingwhereupon said induced flow of fluid will be mixed and blended with saidduct fluid prior to discharge thereof through said other aperture intosaid space.

2. A fluid blending structure comprising a housing having a pair ofspaced apart apertures in one wall thereof, a duct extending into saidhousing and having an outlet adjacent one of said apertures and directedtowards the other of said apertures, an angularly adjustable shutter insaid duct to control the flow of fluid therethrough, means to rotatesaid shutter including an actuator extending through one wall of saidduct, a casing having a first passage receiving said actuator, and asecond passage intersecting said first passage, said second passage alsointersecting said one Wall of said housing, a crank pivoted on saidcasing having one arm in said first passage connected to said actuatorand a second arm in said second passage, a thermostat in said secondpassage engaging said second arm to control said actuatorthermostatically, said casing having a third passage intersecting saidduct on the upstream side of said shutter and intersecting said firstpassage, said first passage having an outlet opening into said housingand being in registry with said third passage, whereby the flow of fluidfrom said duct through said outlet will induce a flow of fluid from saidfirst passage, thereby to aspirate fluid from exteriorly of said housingthrough said second passage past said ther- 7 mostat, the' discharge ofuid from said duct into said housing operating to induce a ow of uidfrom interiorly of said housing through said one aperture into saidhousing, whereupon said induced ow of uid will be mixed with said uiddischarged from said duct prior yto discharge through said otherVaperture into said space.'

References Cited in the file of: this patent UNITED STATES PATENTS1,296,968 Klein Mar. 11,1919

8 Ryan g Dec. 14, Fina -s June 14, Copping Sept. 26, Copping Sept. 26,

M acCracken Dec. 25,

